Services

Oxylipins Analysis Service

Oxylipins are defined as oxygenated metabolites derived from poly-unsaturated fatty acids (PUFAs) such as arachidonic acid (AA), eicosapentaenoic acid (EPA), linoleic acid (LA), and dihomo-γ-linolenic acid (DGLA) and docosahexaenoic acid (DHA). These PUFAs are transformed into a variety of oxylipins through either enzymatic or non-enzymatic oxidation processes. Three main classes of enzymes- cytochrome P450 (CYP450), cyclooxygenase (COX) and lipoxygenase (LOX) -play important roles in the generation of the complex pool of bioactive components from the different precursor PUFAs. Eicosanoids, the best-described lipid mediators, are those biologically active lipid mediators derived from C20 fatty acids, such as prostaglandins, thromboxanes, leukotrienes and related oxygenated derivatives. Oxylipins, affect a broad range of biological processes such as host defense, tissue injury, and surgical intervention and responses to cardiovascular diseases.

Figure. Overview of the oxylipin biosynthesis pathway in plants (abbreviations are explained in the text) Adopt from: lipidlibrary.aocs.org

It still remains a challenge for modern analytical techniques to cover a wide range of these highly bioactive compounds. Immunoassays, either radioimmunoassay, enzyme immunoassays, or luminescent immunoassays, are performed as a common approach. Mostly, they are specific and only focus on one or only few compounds. For example, GC-MS technology provides a sensitive methodology for a wide range of oxylipins. However, derivatization steps, which can lead to additional modification, are essential to increase volatility. To avoid additional modifications, liquid chromatography-mass spectrometric (LC-MS) technique comes into being as one of the most sensitive and specific tools to simultaneously study analogous analytes. LC-MS/MS methods have also been described for identification and quantification of low abundant oxylipins using multiple reaction monitoring (MRM) (ion selective mode).

However, the bioactive lipids of different origins are produced within the same cascade reaction and cross-linked in a complex regulatory network. Therefore, the complex combination of structurally and chemically related oxylipins derived from the different PUFAs has become a challenge for modern LC-MS/MS techniques. The development of analytical oxylipins platform will provide valuable information on metabolites derived from different PUFAs and contribute greatly to our knowledge on inflammation processes. Creative Proteomics expands LC-MS/MS to include a broader range of oxylipins by demonstrating (dMRM) mode to focus on short retention time windows and thus enhance sensitivity. This platform helps researchers to understand and monitor physiological levels of a broad range of oxylipins and related metabolites derived from different PUFAs in plasma and tissues. Our comprehensive platform allows for the quantitative evaluation of more than 100 oxylipins.

Platform

LC-MS/MS

Summary

Identifiation and quantification of more than 100 Oxylipins in plasma or tissue. Oxylipins are extracted and concentrated using solid phase extraction. The eluent is then dried and re-suspended for LCMS separation by RPLC. Finally, the analytes are quantified by ESI- QQQ MRM methods.

Sample Requirement

Normal Volume: 20 mg tissue, 200uL plasma, 1e7 cells

Minimal Volume: 5 mg tissue, 50uL plasma, 6 e6 cells

Report

A detailed technical report will be provided at the end of the whole project, including the experiment procedure, MS/MS instrument parameters

Analytes are reported as uM or ug/mg (tissue), and CV's are generally<20%

The name of the analytes, abbreviation, formula, molecular weight and CAS# would also be included in the report.